Diazabicyclooctane compounds

ABSTRACT

The present invention relates to compounds according to Formula (II): 
                         
or a stereoisomer, tautomer or pharmaceutically acceptable salt or ester thereof, wherein A, R 1  and R 2  are defined herein. Also described are pharmaceutically acceptable compositions of Formula (II) compounds as well as methods for utilizing the compounds of Formula (II) and the pharmaceutically acceptable compositions of Formula (II) compounds as antibacterial agents and β-lactamase inhibitors, useful in the treatment of infectious diseases.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application No. 62/405,332 filed Oct. 7, 2016, the contents of which are herein incorporated by reference in their entirety.

ACKNOWLEDGMENT OF GOVERNMENT SUPPORT

This invention was made with government support under Contract No. HHSO100201600038C awarded by the U.S. Department of Health and Human Services. The government has certain rights in the invention.

FIELD

The present invention relates to compounds formed from the reaction of optically active diazabicyclooctane derivatives and β-lactams.

BACKGROUND

Penicillins and cephalosporins are β-lactam antibiotics that are widely and frequently used in the clinic. However, the acquisition of resistance to β-lactam antibiotics by various pathogens has had a damaging effect on maintaining the effective treatment of bacterial infections. The most significant known mechanism related to the acquisition of bacterial resistance is the production of class A, C, and D β-lactamases having a serine residue at the active center. These enzymes decompose the β-lactam antibiotic, resulting in the loss of the antimicrobial activities. Class A β-lactamases preferentially hydrolyze penicillins while class C β-lactamases have a substrate profile favoring cephalosporins.

Commercially available β-lactamase inhibitors, e.g., clavulanic acid, sulbactam, and tazobactam, are known inhibitors effective mainly against class A β-lactamase producing bacteria, and are used as a mixture with a β-lactam antibiotic. However, many hundreds or more of β-lactamases have been reported to date, including those from resistant bacteria which produce class A KPC-2 β-lactamase decomposing even carbapenems.

In recent years, infectious diseases caused by the above-mentioned resistant bacteria as pathogenic bacteria are found not only in severe infectious disease but also occasionally in community-acquired infectious disease. The currently available antibiotics and β-lactamase inhibitors are progressively becoming ineffective against the incessantly increasing activities of constantly mutating bacterial β-lactamases and as such novel β-lactamase inhibitors and other antibacterial agents are required for the demanding treatment of infectious diseases caused by resistant bacteria.

SUMMARY

The invention is directed to antibacterial agents and β-lactamase inhibitors, useful in the treatment of infectious diseases.

The invention is also directed to a β-lactamase inhibitor effective for the β-lactamase producing bacteria, particularly for the class A, class C and class D β-lactamases. In one embodiment the β-lactamase inhibitor may also recover the antimicrobial activity of a β-lactam antibiotic against the resistant bacteria when used in combination with the β-lactam antibiotic.

In one embodiment the invention is directed to an antibacterial agent or β-lactamase inhibitor that is a compound formed between a reaction of a compound of Formula (I) and a β-lactam, wherein Formula (I) is

wherein

R¹ is benzyl, H or SO₃M; and

M is H, an inorganic cation or an organic cation, or a pharmaceutically acceptable salt or ester thereof.

In one embodiment, R¹ is SO₃M, wherein M is H.

In another embodiment the β-lactam is a β-lactam antibiotic and comprises a core selected from penam, carbapenam, oxapenam, penem, carbapenem, monobactam, cephem, carbacephem and oxacephem.

In another embodiment the β-lactam antibiotic is selected from ampicillin, amoxicillin, azidocillin, azlocillin, aztreonam, biapenem, carbeniccilin, carfecillin, carindacillin, carumonam, cefepime, cefotaxim, cefsumide, ceftaroline, ceftolozane ceftriaxone, ceftazidime, cephem, doripenem, ertapenem, flomoxef, meropenem, piperacillin, tazobactam, ticarcillin, and tigermonam, or pharmaceutically acceptable salts or esters thereof.

In yet another embodiment the β-lactam antibiotic is meropenem, or a pharmaceutically acceptable salt or ester thereof.

In another aspect the present invention is directed to a compound of Formula (II):

wherein

-   R¹ is benzyl, H or SO₃M; -   M is H, or an inorganic or organic cation; -   R² is H, (C₁-C₈)alkyl, —NHC(O)CH₂-aryl, —NHC(O)CH₂-heteroaryl,     —NHC(O)CH(NH₂)-aryl or —NHC(O)(CH₂)₃CH(NH₂)—CO₂R³; -   A is a 5- to 6-membered heterocyclic ring containing at least one     nitrogen atom and substituted with one or more groups selected from     halogen, CN, (C₁-C₈)alkyl, (C₁-C₈)haloalkyl, (C₂-C₈)alkenyl,     (C₂-C₈)alkynyl, OR³, NR³R³, C(O)R³, [(C₁-C₈)alkylene]OR³,     [(C₁-C₈)alkylene]OC(O)R³, [(C₁-C₈)alkylene]OC(O)NR³R³,     [(C₁-C₈)alkylene]NR³R³, C(O)NR³R³, C(O)[(C₁-C₈)alkylene]NR³R³,     CO₂R³, C(S)NR³R³, SR³, S(O)R³, SO₂R³ and SO₂NR³R³; -   R³ is independently H, (C₁-C₈)alkyl, (C₁-C₈)haloalkyl, cycloalkyl,     heterocyclyl, [(C₁-C₈)alkylene]heterocyclyl, aryl,     [(C₁-C₈)alkylene]aryl or heteroaryl; and     -   wherein any alkyl, cycloalkyl, heterocyclyl, heteroaryl or aryl         is optionally substituted with 1, 2, or 3 groups selected from         OH, CN, SH, SO₂NH₂, halogen, NH₂, NHCNH, C(O)NH₂, C(O)N(CH₃)₂,         C(O)NH(aryl-COOH), C(NH)CH₃, CH₂(NH)SO₂NH₂, COOH, COOCH₃,         acetyl, (C₁-C₈)alkyl, O(C₁-C₈)alkyl, S(C₁-C₈)alkyl,         (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, (C₁-C₈)haloalkyl,         (C₁-C₈)thioalkyl and heterocyclyl.

In one embodiment R¹ is SO₃M.

In one embodiment R² is (C₁-C₈)alkyl.

In one embodiment A is a 5-membered heterocyclic ring containing one nitrogen atom. In another embodiment A is a 5-membered heterocyclic ring containing one nitrogen atom and one oxygen atom. In another embodiment A is a 5-membered heterocyclic ring containing one sulfur atom.

In one embodiment A is a 5-membered heterocyclic ring containing one nitrogen atom and substituted with (C₁-C₈)alkyl, COOH or SR³, wherein R³ is heterocyclyl.

In one embodiment a compound of Formula (II) is

or a pharmaceutically acceptable salt or ester thereof.

In another embodiment compositions are disclosed comprising a compound of Formula (II) in combination with a pharmaceutically acceptable carrier, diluent or excipient.

The compounds are useful in the treatment of bacterial infections in humans or animals either alone or in combination with β-lactam antibiotics and/or with other non β-lactam antibiotics.

These and other aspects of the invention will be apparent upon reference to the following detailed description. To this end, various references are set forth herein which describe in more detail certain background information, procedures, compounds and/or compositions, and are each hereby incorporated by reference in their entirety.

DETAILED DESCRIPTION

In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, one skilled in the art will understand that the invention may be practiced without these details. Unless the context requires otherwise, throughout the present specification and claims, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense (i.e., as “including, but not limited to”).

Reference throughout this specification to “one embodiment” or “an embodiment”means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Definitions

As used herein, and unless noted to the contrary, the following terms and phrases have the meaning noted below.

“Amino” refers to the —NH₂ substituent.

“Aminocarbonyl” refers to the —C(O)NH₂ substituent.

“Carboxyl” refers to the —CO₂H substituent.

“Carbonyl” refers to a —C(O)— or —C(═O)— group. Both notations are used interchangeably within the specification.

“Cyano” refers to the —C≡N substituent.

“Cyanoalkylene” refers to the -(alkylene)C≡N substituent.

“Acetyl” refers to the —C(O)CH₃ substituent.

“Hydroxy” or “hydroxyl” refers to the —OH substituent.

“Oxo” refers to an oxygen of —O— substituent.

“Alkyl” refers to a saturated, straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, having from one to twelve carbon atoms (C₁-C₁₂ alkyl), from one to eight carbon atoms (C₁-C₈ alkyl) or from one to six carbon atoms (C₁-C₆ alkyl), and which is attached to the rest of the molecule by a single bond. Exemplary alkyl groups include methyl, ethyl, n-propyl, 1-methylethyl (iso-propyl), n-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl), 3-methylhexyl, 2-methylhexyl, and the like.

“Lower alkyl” has the same meaning as alkyl defined above but having from one to four carbon atoms (C₁-C₄ alkyl).

“Alkylene” or “alkylene chain” refers to a straight or branched divalent hydrocarbon (alkyl) chain linking the rest of the molecule to a radical group, consisting solely of carbon and hydrogen, respectively. Alkylenes can have from one to twelve carbon atoms, e.g., methylene, ethylene, propylene, n-butylene, and the like. The alkylene chain is attached to the rest of the molecule through a single or double bond. The points of attachment of the alkylene chain to the rest of the molecule can be through one carbon or any two carbons within the chain. “Optionally substituted alkylene” refers to alkylene or substituted alkylene.

“Alkoxy” refers to a radical of the formula —OR_(a) where R_(a) is an alkyl having the indicated number of carbon atoms as defined above. Examples of alkoxy groups include without limitation —O-methyl (methoxy), —O-ethyl (ethoxy), —O-propyl (propoxy), —O-isopropyl (iso propoxy) and the like.

“Acyl” refers to a radical of the formula —C(O)R_(a) where R_(a) is an alkyl having the indicated number of carbon atoms.

“Aryl” refers to a hydrocarbon ring system radical comprising hydrogen, 6 to 18 carbon atoms and at least one aromatic ring. Exemplary aryls are hydrocarbon ring system radical comprising hydrogen and 6 to 9 carbon atoms and at least one aromatic ring; hydrocarbon ring system radical comprising hydrogen and 9 to 12 carbon atoms and at least one aromatic ring; hydrocarbon ring system radical comprising hydrogen and 12 to 15 carbon atoms and at least one aromatic ring; or hydrocarbon ring system radical comprising hydrogen and 15 to 18 carbon atoms and at least one aromatic ring. For purposes of this invention, the aryl radical may be a monocyclic, bicyclic, tricyclic or tetracyclic ring system, which may include fused or bridged ring systems. Aryl radicals include, but are not limited to, aryl radicals derived from aceanthrylene, acenaphthylene, acephenanthrylene, anthracene, azulene, benzene, chrysene, fluoranthene, fluorene, as-indacene, s-indacene, indane, indene, naphthalene, phenalene, phenanthrene, pleiadene, pyrene, and triphenylene. “Optionally substituted aryl” refers to an aryl group or a substituted aryl group.

“Cycloalkyl” refers to a stable non-aromatic monocyclic or polycyclic hydrocarbon radical consisting solely of carbon and hydrogen atoms, which may include fused or bridged ring systems, having from three to fifteen carbon atoms, preferably having from three to ten carbon atoms, three to nine carbon atoms, three to eight carbon atoms, three to seven carbon atoms, three to six carbon atoms, three to five carbon atoms, a ring with four carbon atoms, or a ring with three carbon atoms. The cycloalkyl ring may be saturated or unsaturated and attached to the rest of the molecule by a single bond. Monocyclic radicals include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Polycyclic radicals include, for example, adamantyl, norbornyl, decalinyl, 7,7-dimethyl-bicyclo[2.2.1]heptanyl, and the like.

“Fused” refers to any ring structure described herein which is fused to an existing ring structure in the compounds of the invention. When the fused ring is a heterocyclyl ring or a heteroaryl ring, any carbon atom on the existing ring structure which becomes part of the fused heterocyclyl ring or the fused heteroaryl ring may be replaced with a nitrogen atom.

“Halo” or “halogen” refers to bromo (bromine), chloro (chlorine), fluoro (fluorine), or iodo (iodine).

“Haloalkyl” refers to an alkyl radical having the indicated number of carbon atoms, as defined herein, wherein one or more hydrogen atoms of the alkyl group are substituted with a halogen (halo radicals), as defined above. The halogen atoms can be the same or different. Exemplary haloalkyls are trifluoromethyl, difluoromethyl, trichloromethyl, 2,2,2-trifluoroethyl, 1,2-difluoroethyl, 3-bromo-2-fluoropropyl, 1,2-dibromoethyl, and the like.

“Heterocyclyl”, heterocycle”, or “heterocyclic ring” refers to a stable 3- to 18-membered saturated or unsaturated radical which consists of two to twelve carbon atoms and from one to six heteroatoms, for example, one to five heteroatoms, one to four heteroatoms, one to three heteroatoms, or one to two heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur. Exemplary heterocycles include without limitation stable 3-15 membered saturated or unsaturated radicals, stable 3-12 membered saturated or unsaturated radicals, stable 3-9 membered saturated or unsaturated radicals, stable 8-membered saturated or unsaturated radicals, stable 7-membered saturated or unsaturated radicals, stable 6-membered saturated or unsaturated radicals, or stable 5-membered saturated or unsaturated radicals.

Unless stated otherwise specifically in the specification, the heterocyclyl radical may be a monocyclic, bicyclic, tricyclic or tetracyclic ring system, which may include fused or bridged ring systems; and the nitrogen, carbon or sulfur atoms in the heterocyclyl radical may be optionally oxidized; the nitrogen atom may be optionally quaternized; and the heterocyclyl radical may be partially or fully saturated. Examples of non-aromatic heterocyclyl radicals include, but are not limited to, azetidinyl, dioxolanyl, thienyl[1,3]dithianyl, decahydroisoquinolyl, imidazolinyl, imidazolidinyl, isothiazolidinyl, isoxazolidinyl, morpholinyl, octahydroindolyl, octahydroisoindolyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolidinyl, oxazolidinyl, piperidinyl, piperazinyl, 4-piperidonyl, pyrrolidinyl, pyrazolidinyl, quinuclidinyl, thiazolidinyl, tetrahydrofuryl, thietanyl, trithianyl, tetrahydropyranyl, thiomorpholinyl, thiamorpholinyl, 1-oxo-thiomorpholinyl, and 1,1-dioxo-thiomorpholinyl. Heterocyclyls include heteroaryls as defined herein, and examples of aromatic heterocyclyls are listed in the definition of heteroaryls below.

“Heteroaryl” or “heteroarylene” refers to a 5- to 14-membered ring system radical comprising hydrogen atoms, one to thirteen carbon atoms, one to six heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, and at least one aromatic ring. For purposes of this invention, the heteroaryl radical may be a stable 5-12 membered ring, a stable 5-10 membered ring, a stable 5-9 membered ring, a stable 5-8 membered ring, a stable 5-7 membered ring, or a stable 6 membered ring that comprises at least 1 heteroatom, at least 2 heteroatoms, at least 3 heteroatoms, at least 4 heteroatoms, at least 5 heteroatoms or at least 6 heteroatoms. Heteroaryls may be a monocyclic, bicyclic, tricyclic or tetracyclic ring system, which may include fused or bridged ring systems; and the nitrogen, carbon or sulfur atoms in the heteroaryl radical may be optionally oxidized; the nitrogen atom may be optionally quaternized. The heteroatom may be a member of an aromatic or non-aromatic ring, provided at least one ring in the heteroaryl is aromatic. Examples include, but are not limited to, azepinyl, acridinyl, benzimidazolyl, benzothiazolyl, benzindolyl, benzodioxolyl, benzofuranyl, benzooxazolyl, benzothiazolyl, benzothiadiazolyl, benzo[b][1,4]dioxepinyl, 1,4-benzodioxanyl, benzonaphthofuranyl, benzoxazolyl, benzodioxolyl, benzodioxinyl, benzopyranyl, benzopyranonyl, benzofuranyl, benzofuranonyl, benzothienyl (benzothiophenyl), benzotriazolyl, benzo[4,6]imidazo[1,2-a]pyridinyl, carbazolyl, cinnolinyl, dibenzofuranyl, dibenzothiophenyl, furanyl, furanonyl, isothiazolyl, imidazolyl, indazolyl, indolyl, indazolyl, isoindolyl, indolinyl, isoindolinyl, isoquinolyl, indolizinyl, isoxazolyl, naphthyridinyl, oxadiazolyl, 2-oxoazepinyl, oxazolyl, oxiranyl, 1-oxidopyridinyl, 1-oxidopyrimidinyl, 1-oxidopyrazinyl, 1-oxidopyridazinyl, 1-phenyl-1H-pyrrolyl, phenazinyl, phenothiazinyl, phenoxazinyl, phthalazinyl, pteridinyl, purinyl, pyrrolyl, pyrazolyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, quinazolinyl, quinoxalinyl, quinolinyl, quinuclidinyl, isoquinolinyl, tetrahydroquinolinyl, thiazolyl, thiadiazolyl, triazolyl, tetrazolyl, triazinyl, and thiophenyl (i.e. thienyl).

“Sulfoxide” refers to a —S(O)— group in which the sulfur atom is covalently attached to two carbon atoms.

“Sulfone” refers to a —S(O)₂— group in which a hexavalent sulfur is attached to each of the two oxygen atoms through double bonds and is further attached to two carbon atoms through single covalent bonds.

The compound of the invention can exist in various isomeric forms, as well as in one or more tautomeric forms, including both single tautomers and mixtures of tautomers. The term “isomer” is intended to encompass all isomeric forms of a compound of this invention, including tautomeric forms of the compound.

Some compounds described here can have asymmetric centers and therefore exist in different enantiomeric and diastereomeric forms. A compound of the invention can be in the form of an optical isomer or a diastereomer. Accordingly, the invention encompasses compounds of the invention and their uses as described herein in the form of their optical isomers, diastereoisomers and mixtures thereof, including a racemic mixture. Optical isomers of the compounds of the invention can be obtained by known techniques such as asymmetric synthesis, chiral chromatography, or via chemical separation of stereoisomers through the employment of optically active resolving agents.

Unless otherwise indicated, “stereoisomer” means one stereoisomer of a compound that is substantially free of other stereoisomers of that compound. Thus, a stereomerically pure compound having one chiral center will be substantially free of the opposite enantiomer of the compound. A stereomerically pure compound having two chiral centers will be substantially free of other diastereomers of the compound. A typical stereomerically pure compound comprises greater than about 80% by weight of one stereoisomer of the compound and less than about 20% by weight of other stereoisomers of the compound, for example greater than about 90% by weight of one stereoisomer of the compound and less than about 10% by weight of the other stereoisomers of the compound, or greater than about 95% by weight of one stereoisomer of the compound and less than about 5% by weight of the other stereoisomers of the compound, or greater than about 97% by weight of one stereoisomer of the compound and less than about 3% by weight of the other stereoisomers of the compound.

If there is a discrepancy between a depicted structure and a name given to that structure, then the depicted structure controls. Additionally, if the stereochemistry of a structure or a portion of a structure is not indicated with, for example, bold or dashed lines, the structure or portion of the structure is to be interpreted as encompassing all stereoisomers of it. In some cases, however, where more than one chiral center exists, the structures and names may be represented as single enantiomers to help describe the relative stereochemistry. Those skilled in the art of organic synthesis will know if the compounds are prepared as single enantiomers from the methods used to prepare them.

In this description, a “pharmaceutically acceptable salt” is a pharmaceutically acceptable, organic or inorganic acid or base salt of a compound of the invention. Representative pharmaceutically acceptable salts include, e.g., alkali metal salts, alkali earth salts, ammonium salts, water-soluble and water-insoluble salts, such as the acetate, amsonate (4,4-diaminostilbene-2,2-disulfonate), benzenesulfonate, benzonate, bicarbonate, bisulfate, bitartrate, borate, bromide, butyrate, calcium, calcium edetate, camsylate, carbonate, chloride, citrate, clavulariate, dihydrochloride, edetate, edisylate, estolate, esylate, fiunarate, gluceptate, gluconate, glutamate, glycollylarsanilate, hexafluorophosphate, hexylresorcinate, hydrabamine, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, isothionate, lactate, lactobionate, laurate, malate, maleate, mandelate, mesylate, methylbromide, methylnitrate, methylsulfate, mucate, napsylate, nitrate, N-methylglucamine ammonium salt, 3-hydroxy-2-naphthoate, oleate, oxalate, palmitate, pamoate (1,1-methene-bis-2-hydroxy-3-naphthoate, einbonate), pantothenate, phosphate/diphosphate, picrate, polygalacturonate, propionate, p-toluenesulfonate, salicylate, stearate, subacetate, succinate, sulfate, sulfosaliculate, suramate, tannate, tartrate, teoclate, tosylate, triethiodide, and valerate salts. A pharmaceutically acceptable salt can have more than one charged atom in its structure. In this instance the pharmaceutically acceptable salt can have multiple counterions. Thus, a pharmaceutically acceptable salt can have one or more charged atoms and/or one or more counterions.

The terms “treat”, “treating” and “treatment” refer to the amelioration or eradication of a disease or symptoms associated with an infectious disease. In certain embodiments, such terms refer to minimizing the spread or worsening of the infectious disease resulting from the administration of one or more prophylactic or therapeutic agents to a patient with such a infectious disease.

The term “effective amount” refers to an amount of a compound of the invention or other active ingredient sufficient to provide a therapeutic or prophylactic benefit in the treatment or prevention of an infectious disease or to delay or minimize symptoms associated with an infectious disease. Further, a therapeutically effective amount with respect to a compound of the invention means that amount of therapeutic agent alone, or in combination with other therapies, that provides a therapeutic benefit in the treatment or prevention of an infectious disease. Used in connection with a compound of the invention, the term can encompass an amount that improves overall therapy, reduces or avoids symptoms or causes of disease, or enhances the therapeutic efficacy or synergies with another therapeutic agent.

A “patient” or subject” includes an animal, such as a human, cow, horse, sheep, lamb, pig, chicken, turkey, quail, cat, dog, mouse, rat, rabbit or guinea pig. The animal can be a mammal such as a non-primate and a primate (e.g., monkey and human). In one embodiment, a patient is a human, such as a human infant, child, adolescent or adult.

The term “prodrug” refers to a precursor of a drug that is a compound which upon administration to a patient must undergo chemical conversion by metabolic processes before becoming an active pharmacological agent. Exemplary prodrugs of compounds in accordance with Formula (II) are esters, acetamides, and amides.

The inventive compounds according to Formula (II) may be isotopically-labelled by having one or more atoms replaced by an atom having a different atomic mass or mass number. Examples of isotopes that can be incorporated into compounds of according to Formula (II) include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine, chlorine, or iodine. Illustrative of such isotopes are ²H, ³H, ¹¹C, ¹³C, ¹⁴C, ¹³N, ¹⁵N, ¹⁵O, ¹⁷O, ¹⁸O, ³¹P, ³²P, ³⁵S, ¹⁸F, ³⁶Cl, ¹²³I, and ¹²⁵I, respectively. These radiolabelled compounds can be used to measure the biodistribution, tissue concentration and the kinetics of transport and excretion from biological tissues including a subject to which such a labelled compound is administered. Labeled compounds are also used to determine therapeutic effectiveness, the site or mode of action, and the binding affinity of a candidate therapeutic to a pharmacologically important target. Certain radioactive-labelled compounds according to Formula (I), therefore, are useful in drug and/or tissue distribution studies. The radioactive isotopes tritium, i.e. ³H, and carbon-14, i.e. ¹⁴C, are particularly useful for this purpose in view of their ease of incorporation and ready means of detection.

Substitution with heavier isotopes such as deuterium, i.e. ²H, affords certain therapeutic advantages resulting from the greater metabolic stability, for example, increased in vivo half-life of compounds containing deuterium. Substitution of hydrogen with deuterium may reduce dose required for therapeutic effect, and hence may be preferred in a discovery or clinical setting.

Substitution with positron emitting isotopes, such as ¹¹C, ¹⁸F, ¹⁵O and ¹³N, provides labeled analogs of the inventive compounds that are useful in Positron Emission Tomography (PET) studies, e.g., for examining substrate receptor occupancy. Isotopically-labeled compounds according to Formula (II) can generally be prepared by conventional techniques known to those skilled in the art or by processes analogous to those described in the Preparations and Examples section as set out below using an appropriate isotopic-labeling reagent.

Embodiments of the invention disclosed herein are also meant to encompass the in vivo metabolic products of compounds according to Formula (II). Such products may result from, for example, the oxidation, reduction, hydrolysis, amidation, esterification, and like processes primarily due to enzymatic activity upon administration of a compound of the invention. Accordingly, the invention includes compounds that are produced as by-products of enzymatic or non-enzymatic activity on an inventive compound following the administration of such a compound to a mammal for a period of time sufficient to yield a metabolic product. Metabolic products, particularly pharmaceutically active metabolites are typically identified by administering a radiolabelled compound of the invention in a detectable dose to a subject, such as rat, mouse, guinea pig, monkey, or human, for a sufficient period of time during which metabolism occurs, and isolating the metabolic products from urine, blood or other biological samples that are obtained from the subject receiving the radiolabelled compound.

The invention also provides pharmaceutically acceptable salt forms of Formula (II) compounds. Encompassed within the scope of the invention are both acid and base addition salts that are formed by contacting a pharmaceutically suitable acid or a pharmaceutically suitable base with a compound of the invention.

To this end, a “pharmaceutically acceptable acid addition salt” refers to those salts which retain the biological effectiveness and properties of the free bases, which are not biologically or otherwise undesirable, and which are formed with inorganic acids such as, but are not limited to, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like, and organic acids such as, but not limited to, acetic acid, 2,2-dichloroacetic acid, adipic acid, alginic acid, ascorbic acid, aspartic acid, benzenesulfonic acid, benzoic acid, 4-acetamidobenzoic acid, camphoric acid, camphor-10-sulfonic acid, capric acid, caproic acid, caprylic acid, carbonic acid, cinnamic acid, citric acid, cyclamic acid, dodecylsulfuric acid, ethane-1,2-disulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, formic acid, fumaric acid, galactaric acid, gentisic acid, glucoheptonic acid, gluconic acid, glucuronic acid, glutamic acid, glutaric acid, 2-oxo-glutaric acid, glycerophosphoric acid, glycolic acid, hippuric acid, isobutyric acid, lactic acid, lactobionic acid, lauric acid, maleic acid, malic acid, malonic acid, mandelic acid, methanesulfonic acid, mucic acid, naphthalene-1,5-disulfonic acid, naphthalene-2-sulfonic acid, 1-hydroxy-2-naphthoic acid, nicotinic acid, oleic acid, orotic acid, oxalic acid, palmitic acid, pamoic acid, propionic acid, pyroglutamic acid, pyruvic acid, salicylic acid, 4-aminosalicylic acid, sebacic acid, stearic acid, succinic acid, tartaric acid, thiocyanic acid, p-toluenesulfonic acid, trifluoroacetic acid, undecylenic acid, and the like.

Similarly, a “pharmaceutically acceptable base addition salt” refers to those salts which retain the biological effectiveness and properties of the free acids, which are not biologically or otherwise undesirable. These salts are prepared by addition of an inorganic base or an organic base to the free acid. Salts derived from inorganic bases include, but are not limited to, the sodium, potassium, lithium, ammonium, calcium, magnesium, iron, zinc, copper, manganese, aluminum salts and the like. Preferred inorganic salts are the ammonium, sodium, potassium, calcium, and magnesium salts. Salts derived from organic bases include, but are not limited to, salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines and basic ion exchange resins, such as ammonia, isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine, diethanolamine, ethanolamine, deanol, 2-dimethylaminoethanol, 2-diethylaminoethanol, dicyclohexylamine, lysine, arginine, histidine, caffeine, procaine, hydrabamine, choline, betaine, benethamine, benzathine, ethylenediamine, glucosamine, methylglucamine, theobromine, triethanolamine, tromethamine, purines, piperazine, piperidine, N-ethylpiperidine, polyamine resins and the like. Particularly preferred organic bases are isopropylamine, diethylamine, ethanolamine, trimethylamine, dicyclohexylamine, choline and caffeine.

Often crystallizations produce a solvate of the compound of the invention. As used herein, the term “solvate” refers to an aggregate that comprises one or more molecules of a compound of the invention with one or more molecules of solvent. The solvent may be water, in which case the solvate may be a hydrate. Alternatively, the solvent may be an organic solvent. Thus, the compounds of the present invention may exist as a hydrate, including a monohydrate, dihydrate, hemihydrate, sesquihydrate, trihydrate, tetrahydrate and the like, as well as the corresponding solvated forms. The compounds of the invention may be true solvates, while in other cases, the compounds of the invention may merely retain adventitious water or be a mixture of water plus some adventitious solvent.

A “stereoisomer” refers to a compound made up of the same atoms bonded by the same bonds but having different three-dimensional structures, which are not interchangeable. The present invention contemplates various stereoisomers and mixtures thereof and includes “enantiomers”, which refers to two stereoisomers whose molecules are nonsuperimposeable mirror images of one another.

Compounds of the invention, or their pharmaceutically acceptable salts may contain one or more asymmetric centers and may thus give rise to enantiomers, diastereomers, and other stereoisomeric forms that may be defined, in terms of absolute stereochemistry, as (R)- or (S)- or, as (D)- or (L)- for amino acids. The present invention is meant to include all such possible isomers, as well as their racemic and optically pure forms. Optically active (+) and (−), (R)- and (S)-, or (D)- and (L)-isomers may be prepared using chiral synthons or chiral reagents, or resolved using conventional techniques, for example, chromatography and fractional crystallization. Conventional techniques for the preparation/isolation of individual enantiomers include chiral synthesis from a suitable optically pure precursor or resolution of the racemate (or the racemate of a salt or derivative) using, for example, chiral high pressure liquid chromatography (HPLC). When the compounds described herein contain olefinic double bonds or other centers of geometric asymmetry, and unless specified otherwise, it is intended that the compounds include both E and Z geometric isomers. Likewise, all tautomeric forms are also intended to be included.

The term “tautomer” refers to a proton shift from one atom of a molecule to another atom of the same molecule.

The inventive compounds are synthesized using conventional synthetic methods, and more specifically using the general methods noted below. Specific synthetic protocols for several compounds in accordance with the present invention are described in the Examples.

Pharmaceutical Formulations

In one embodiment, a compound according to Formula (II) is formulated as pharmaceutically acceptable compositions that contain a Formula (II) compound in an amount effective to treat a particular disease or condition of interest upon administration of the pharmaceutical composition to a mammal. Pharmaceutical compositions in accordance with the present invention can comprise a Formula (II) compound in combination with a pharmaceutically acceptable carrier, diluent or excipient.

In this regard, a “pharmaceutically acceptable carrier, diluent or excipient” includes without limitation any adjuvant, carrier, excipient, glidant, sweetening agent, diluent, preservative, dye/colorant, flavor enhancer, surfactant, wetting agent, dispersing agent, suspending agent, stabilizer, isotonic agent, solvent, or emulsifier which has been approved by the United States Food and Drug Administration as being acceptable for use in humans or domestic animals.

Further, a “mammal” includes humans and both domestic animals such as laboratory animals and household pets (e.g., cats, dogs, swine, cattle, sheep, goats, horses, rabbits), and non-domestic animals such as wildlife and the like.

The pharmaceutical compositions of the invention can be prepared by combining a compound of the invention with an appropriate pharmaceutically acceptable carrier, diluent or excipient, and may be formulated into preparations in solid, semi-solid, liquid or gaseous forms, such as tablets, capsules, powders, granules, ointments, solutions, suppositories, injections, inhalants, gels, microspheres, and aerosols. Typical routes of administering such pharmaceutical compositions include, without limitation, oral, topical, transdermal, inhalation, parenteral, sublingual, buccal, rectal, vaginal, and intranasal. The term parenteral as used herein includes subcutaneous injections, intravenous, intramuscular, intrasternal injection or infusion techniques. Pharmaceutical compositions of the invention are formulated so as to allow the active ingredients contained therein to be bioavailable upon administration of the composition to a patient. Compositions that will be administered to a subject or patient take the form of one or more dosage units, where for example, a tablet may be a single dosage unit, and a container of a compound of the invention in aerosol form may hold a plurality of dosage units. Actual methods of preparing such dosage forms are known, or will be apparent, to those skilled in this art; for example, see Remington: The Science and Practice of Pharmacy, 20th Edition (Philadelphia College of Pharmacy and Science, 2000). The composition to be administered will, in any event, contain a therapeutically effective amount of a compound of the invention, or a pharmaceutically acceptable salt thereof, for treatment of a disease or condition of interest in accordance with the teachings of this invention.

A pharmaceutical composition of the invention may be in the form of a solid or liquid. In one aspect, the carrier(s) are particulate, so that the compositions are, for example, in tablet or powder form. The carrier(s) may be liquid, with the compositions being, for example, an oral syrup, injectable liquid or an aerosol, which is useful in, for example, inhalatory administration. When intended for oral administration, the pharmaceutical composition is preferably in either solid or liquid form, where semi-solid, semi-liquid, suspension and gel forms are included within the forms considered herein as either solid or liquid.

As a solid composition for oral administration, the pharmaceutical composition may be formulated into a powder, granule, compressed tablet, pill, capsule, chewing gum, wafer or the like form. Such a solid composition will typically contain one or more inert diluents or edible carriers. In addition, one or more of the following may be present: binders such as carboxymethylcellulose, ethyl cellulose, microcrystalline cellulose, gum tragacanth or gelatin; excipients such as starch, lactose or dextrins, disintegrating agents such as alginic acid, sodium alginate, Primogel, corn starch and the like; lubricants such as magnesium stearate or Sterotex; glidants such as colloidal silicon dioxide; sweetening agents such as sucrose or saccharin; a flavoring agent such as peppermint, methyl salicylate or orange flavoring; and a coloring agent.

When the pharmaceutical composition is in the form of a capsule, for example, a gelatin capsule, it may contain, in addition to materials of the above type, a liquid carrier such as polyethylene glycol or oil.

The pharmaceutical composition may be in the form of a liquid, for example, an elixir, syrup, solution, emulsion or suspension. The liquid may be for oral administration or for delivery by injection, as two examples. When intended for oral administration, preferred composition contain, in addition to the present compounds, one or more of a sweetening agent, preservatives, dye/colorant and flavor enhancer. In a composition intended to be administered by injection, one or more of a surfactant, preservative, wetting agent, dispersing agent, suspending agent, buffer, stabilizer and isotonic agent may be included.

The liquid pharmaceutical compositions of the invention, whether they be solutions, suspensions or other like form, may include one or more of the following adjuvants: sterile diluents such as water for injection, saline solution, preferably physiological saline, Ringer's solution, isotonic sodium chloride, fixed oils such as synthetic mono or diglycerides which may serve as the solvent or suspending medium, polyethylene glycols, glycerin, propylene glycol or other solvents; antibacterial agents such as benzyl alcohol or methyl paraben; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediaminetetraacetic acid; buffers such as acetates, citrates or phosphates and agents for the adjustment of tonicity such as sodium chloride or dextrose. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic. Physiological saline is a preferred adjuvant. An injectable pharmaceutical composition is preferably sterile.

A liquid pharmaceutical composition of the invention intended for either parenteral or oral administration should contain an amount of a compound of the invention such that a suitable dosage will be obtained.

The pharmaceutical composition of the invention may be intended for topical administration, in which case the carrier may suitably comprise a solution, emulsion, ointment or gel base. The base, for example, may comprise one or more of the following: petrolatum, lanolin, polyethylene glycols, bee wax, mineral oil, diluents such as water and alcohol, and emulsifiers and stabilizers. Thickening agents may be present in a pharmaceutical composition for topical administration. If intended for transdermal administration, the composition may include a transdermal patch or iontophoresis device.

The pharmaceutical composition of the invention may be intended for rectal administration, in the form, for example, of a suppository, which will melt in the rectum and release the drug. The composition for rectal administration may contain an oleaginous base as a suitable nonirritating excipient. Such bases include, without limitation, lanolin, cocoa butter and polyethylene glycol.

The pharmaceutical composition of the invention may include various materials, which modify the physical form of a solid or liquid dosage unit. For example, the composition may include materials that form a coating shell around the active ingredients. The materials that form the coating shell are typically inert, and may be selected from, for example, sugar, shellac, and other enteric coating agents. Alternatively, the active ingredients may be encased in a gelatin capsule.

The pharmaceutical composition of the invention in solid or liquid form may include an agent that binds to the compound of the invention and thereby assists in the delivery of the compound. Suitable agents that may act in this capacity include a monoclonal or polyclonal antibody, a protein or a liposome.

The pharmaceutical composition of the invention may consist of dosage units that can be administered as an aerosol. The term aerosol is used to denote a variety of systems ranging from those of colloidal nature to systems consisting of pressurized packages. Delivery may be by a liquefied or compressed gas or by a suitable pump system that dispenses the active ingredients. Aerosols of compounds of the invention may be delivered in single phase, bi-phasic, or tri-phasic systems in order to deliver the active ingredient(s). Delivery of the aerosol includes the necessary container, activators, valves, subcontainers, and the like, which together may form a kit. One skilled in the art, without undue experimentation may determine preferred aerosols.

The pharmaceutical compositions of the invention may be prepared by any methodology well known in the pharmaceutical art. For example, a pharmaceutical composition intended to be administered by injection can be prepared by combining a compound of the invention with sterile, distilled water so as to form a solution. A surfactant may be added to facilitate the formation of a homogeneous solution or suspension. Surfactants are compounds that non-covalently interact with the compound of the invention so as to facilitate dissolution or homogeneous suspension of the compound in the aqueous delivery system.

Therapeutic Use

The compounds of the invention, or their pharmaceutically acceptable salts or esters, are administered in a therapeutically effective amount, which will vary depending upon a variety of factors including the activity of the specific compound employed; the metabolic stability and length of action of the compound; the age, body weight, general health, sex, and diet of the patient; the mode and time of administration; the rate of excretion; the drug combination; the severity of the particular disorder or condition; and the subject undergoing therapy.

“Effective amount” or “therapeutically effective amount” refers to that amount of a compound of the invention which, when administered to a mammal, preferably a human, is sufficient to effect treatment of an infectious disease in the mammal. The amount of a compound of the invention which constitutes a “therapeutically effective amount” will vary depending on the compound, the condition and its severity, the manner of administration, and the age of the mammal to be treated, but can be determined routinely by one of ordinary skill in the art having regard to his own knowledge and to this disclosure.

Compounds of the invention, or pharmaceutically acceptable salts or esters thereof, may also be administered simultaneously with, prior to, or after administration of one or more other therapeutic agents. Such combination therapy includes administration of a single pharmaceutical dosage formulation which contains a compound of the invention and one or more additional active agents, as well as administration of the compound of the invention and each active agent in its own separate pharmaceutical dosage formulation. For example, a compound of the invention and the other active agent can be administered to the patient together in a single oral dosage composition such as a tablet or capsule, or each agent administered in separate oral dosage formulations. Where separate dosage formulations are used, the compounds of the invention and one or more additional active agents can be administered at essentially the same time, i.e., concurrently, or at separately staggered times, i.e., sequentially; combination therapy is understood to include all these regimens.

Therapeutically effective dosages of a compound according to Formula (II) or a composition of a Formula (II) compound will generally range from about 1 to 2000 mg/day, from about 10 to about 1000 mg/day, from about 10 to about 500 mg/day, from about 10 to about 250 mg/day, from about 10 to about 100 mg/day, or from about 10 to about 50 mg/day. The therapeutically effective dosages may be administered in one or multiple doses. It will be appreciated, however, that specific doses of the compounds of the invention for any particular patient will depend on a variety of factors such as age, sex, body weight, general health condition, diet, individual response of the patient to be treated, time of administration, severity of the disease to be treated, the activity of particular compound applied, dosage form, mode of application and concomitant medication. The therapeutically effective amount for a given situation will readily be determined by routine experimentation and is within the skills and judgment of the ordinary clinician or physician. In any case the compound or composition will be administered at dosages and in a manner which allows a therapeutically effective amount to be delivered based upon patient's unique condition.

The term “β-lactam antibiotic” refers to a compound with antibiotic property that contains a β-lactam functionality. Examples of β-lactam antibiotics which can be used in combination with the compounds of the present invention represented by formula (II) are commonly marketed penicillins, cephalosporins, penems, carbapenems and monobactams.

Examples of β-lactam antibiotics which can be used in combination with the compounds of the present invention represented by formula (II) are commonly used penicillins, such as amoxicillin, ampicillin, azlocillin, mezlocillin, apalcillin, hetacillin, bacampicillin, carbenicillin, sulbenicillin, ticarcillin, piperacillin, methicillin, ciclacillin, talampicillin, oxacillin, cloxacillin, dicloxacillin and commonly used cephalosporins such as cephalothin, cephaloridine, cefaclor, cefadroxil, cefamandole, cefazolin, cephalexin, cephradine, cephapirin, cefuroxime, cefoxitin, cephacetrile, cefotiam, cefotaxime, cefatriazine, cefsulodin, cefoperazone, ceftizoxime, cefmenoxime, cefmetazole, cephaloglycin, cefonicid, cefodizime, cefpirome, cefepime, ceftazidime, cefpiramide, ceftriaxone, cefbuperazone, cefprozil, cefixime, ceftobiprole, ceftaroline, cefalonium, cefminox, ceforanide, cefuzonam, cefoxitin, cefotetan, loracarbef, cefdinir, cefditoren, cefetamet, cefcapene, cefdaloxime, ceftibuten, cefroxadine, latamoxef (moxalactam), and CXA-101. From the carbapenem class of β-lactam antibiotics such as imipenem, meropenem, panipenem, biapenem, doripenem, ertapenem and the like could be used. From monobactam class of β-lactam antibiotics such as aztreonam, carumonam, tigemonam, and the like could be used as the combination partner of antibiotic.

Synthesis

The following examples are provided for purpose of illustration and not limitation.

EXAMPLE 1 (4R,5S)-3-(((3S,5S)-5-(dimethylcarbamoyl)pyrrolidin-3-yl)thio)-5-((2S,3R)-3-hydroxy-1-oxo-1-((2-(((2S,5R)-7-oxo-6-(sulfooxy)-1,6-diazabicyclo[3.2.1]octane-2-carboxamido)oxy)ethyl)amino)butan-2-yl)-4-methyl-4,5-dihydro-1H-pyrrole-2-carboxylic acid

In a 50 ml round-bottomed flask equipped with a with rubber seal, (4R,5S,6S)-3-(((3S,5S)-5-(dimethylcarbamoyl)pyrrolidin-3-yl)thio)-6-((R)-1-hydroxyethyl)-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid or meropenem (Reactant (a), 924 mg, 2.41 mmol), which contains sodium carbonate (383 mg, 3.61 mmol), was dissolved in water (13 ml) rendering a solution having a pH value of ˜8. To this solution, (2S,5R)-2-((2-aminoethoxy)carbamoyl)-7-oxo-1,6-diazabicyclo[3.2.1]octan-6-yl hydrogen sulfate hydrate (Reactant (b), 1.31 g, 3.83 mmol) was added in one portion. A white suspension that was initially formed from the mixing of Reactant (a) and Reactant (b) was stirred at room temperature for 40 h, during which a clear brown solution was formed.

The reaction solvent was removed by lyophilization at ≤room temperature over a period of ca. 20 h to maintain mild conditions. The crude product was recovered as a brown powder, 2.33 g, in 137% yield. HPLC (area %): 14% Reactant (b)+38% Product (c)+8% unknown. The remaining area % was distributed in broad peaks.

A 540 mg aliquot of the crude product aliquot was subjected to a preparative HPLC run. Fractions containing product were collected, combined & freed of solvent by lyophilization at ≤room temperature for a period of over 24 h, furnishing 120 mg of Product (c), a white, wispy web-like material. HPLC (area %): 96%, ¹H-NMR correlates with reference sample.

Antibacterial Activity

Compounds of the present invention, either alone or in combination with one or more antibiotics, are tested for minimum inhibitory concentration (MIC, μg/mL) against various bacteria. Compounds of the present invention can also be tested in combination with various antibiotics against metallo β-lactamase producing bacteria.

β-Lactamase Inhibitory Activity

The inhibitory activities of present compounds against various enzymes are measured by spectrophotometric assay using 490 nM and using nitrocefin as a substrate [J. Antimicrob. Chemother., 28, pp 775-776 (1991)]. The concentration of inhibitor (IC₅₀) which inhibits by 50% the reaction of hydrolysis of nitrocefin by the enzyme is determined.

The various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure. 

The invention claimed is:
 1. A compound of Formula (II)

wherein R¹ is benzyl, H or SO₃M; M is H, or an inorganic or organic cation; R² is H, (C₁-C₈)alkyl, —NHC(O)CH₂-aryl, —NHC(_(O))CH₂-heteroaryl, —NHC(O)CH(NH₂)-aryl or —NHC(O)(CH₂)₃CH(NH₂)—CO₂R³; A is a 5- to 6-membered heterocyclic ring containing at least one nitrogen atom and substituted with one or more groups selected from halogen, CN, (C₁C₈)alkyl, (C₁-C₈)haloalkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, OR³, NR³R³, C(O)R³, [(C₁-C₈)alkylene]OR³, [(C₁-C₈)alkylene]OC(O)R³, [(C₁-C₈)alkylene]OC(O)NR³R³, [(C₁-C₈)alkylene]NR³R³, C(O)NR³R³, C(O)[(C₁-C₈)alkylene]NR³R³, CO₂R³, C(S)NR³R³, SR³, S(O)R³, SO₂R³ and SO₂NR³R³; R³ is independently H, (C₁-C₈)alkyl, (C₁-C₈)haloalkyl, cycloalkyl, heterocyclyl, [(C₁-C₈)alkylene] heterocyclyl, aryl, [(C₁-C₈)alkylene] aryl or heteroaryl; and wherein any alkyl, cycloalkyl, heterocyclyl, heteroaryl or aryl is optionally substituted with 1, 2, or 3 groups selected from OH, CN, SH, SO₂NH_(2,) halogen, NH₂, NHCNH, C(O)NH₂, C(O)N(CH₃)₂, C(O)NH(aryl-COOH), C(NH)CH₃, CH₂(NH)SO₂NH₂, COOH, COOCH₃, acetyl, (C₁-C₈)alkyl, S(C₁-C₈)alkyl, S(C₁-C₈)alkyl, (C₂-C₈)alkenyl, (C₂-C₈)alkynyl, (C₁-C₈)haloalkyl, (C₁-C₈)thioalkyl and heterocyclyl, or a pharmaceutically acceptable salt or ester thereof.
 2. The compound of claim 1 wherein R¹ is SO₃M.
 3. The compound of claim 1 wherein R² is (C₁-C₈)alkyl.
 4. The compound of claim 1 wherein A is a 5-membered heterocyclic ring containing one nitrogen atom.
 5. The compound of claim 1 wherein A is a 5-membered heterocyclic ring containing one nitrogen atom and one oxygen atom.
 6. The compound of claim 1 wherein A is a 5-membered heterocyclic ring containing one nitrogen atom and one sulfur atom.
 7. The compound of claim 1 wherein A is a 5-membered heterocyclic ring containing one nitrogen atom and substituted with (C₁-C₈)alkyl, COOH or SR³, wherein R³ is heterocyclyl.
 8. The compound of claim 1 that is

or a pharmaceutically acceptable salt or ester thereof.
 9. A pharmaceutical composition comprising a compound of Formula (II), according to claim 1, in combination with a pharmaceutically acceptable carrier, diluent or excipient.
 10. A method for treating a bacterial infection in a mammal in need thereof comprising administrating to the mammal (i) a therapeutically effective amount of at least one compound according to claim 1 or a stereoisomer, tautomer or pharmaceutically acceptable salt or ester thereof, or (ii) a pharmaceutical composition of claim
 9. 